I recommend the Portland Design 3 Wrencho big time for the road.

The handle flat being rotated 90 degrees from the head is an excellent design feature. Using the wrench is very comfortable on your hand because of this. But, because the wrench is so short, it can be tough to really crank down rear nuts. The solution I have found is made easier and more stable by the angled handle. I just tighten the nuts to "good-n-snug", put the bike back on it's wheels with the wrench on a nut and give it it a downward press with my foot.

Plus it looks cool, black and smooth, like a slick tire.